What Have we Learned?
Information from the Neotripical Flyways Project
In 2018, a literature review was published that synthesized current knowledge of major stopover sites in Central and South America. Although several sites and bottleneck locations are well known, several major gaps in our knowledge were identified, such as the major stopovers for diurnally migrating aerial insectivores.
In 2019, a study of Gray-cheeked Thrushes, Catharus minimus,found that multiple populations of Gray-cheeked Thrushes converged in northern Colombia within an area spanning less than 1% of their breeding range. Arrival date and body condition upon arrival at stopover sites was largely determined by breeding (but not winter) origin, sex, and age. These findings indicate a significant travel bottleneck near Central America that may have effects on overall population fitness and survival.